A244362 - OEIS

%I #17 Oct 23 2014 21:06:16

%S 2,6,12,20,28,40,50,66,82,102,116,140,156,182,208,240,260,296,318,358,

%T 394,432,458,506,540,584,628,684

%N Total number of toothpicks after n-th stage in the toothpick structure of the symmetric representation of sigma in the first quadrant (without the axes x and y).

%C Partial sums of A244363.

%F a(n) = 2*A244360(n).

%F a(n) = A244370(n)/4. - _Omar E. Pol_, Oct 18 2014

%e Illustration of the structure after 7 stages (Contains 50 toothpicks):

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%e .     1 2 3 4 5 6 7

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%Y Cf. A000203, A237270, A237271, A237593, A244360, A244361, A244363, A244370, A244371.

%K nonn,more

%O 1,1

%A _Omar E. Pol_, Jun 26 2014

%E More terms from _Omar E. Pol_, Oct 18 2014